1-(chloromethoxy)-2-methylpropane

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1.9 g (14.08 mmol) of potassium carbonate were added at 60° C. to a suspension of 2.25 g (8.8 mmol) of 7-benzyl-3-methylxanthine (prepared according to Example 1 a) in 50 ml of N-methylpyrrolidone and the mixture was stirred at this temperature for one hour. 1.4 g (11.44 mmol) of isobutoxymethyl chloride were then added dropwise and the mixture was stirred at 80° C. for 3 hours. A further 0.5 g (4.4 mmol) of isobutoxymethyl chloride was then added and the mixture was stirred again for 2 hours. 50 ml of water were then added and the mixture was extracted three times using 60 ml of methyl tert-butyl ether each time. The combined organic phases were washed twice with 30 ml of water each time, dried using magnesium sulfate and concentrated under reduced pressure. The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2). prepared the mixture was stirred at 80° C. for 3 hours the mixture was stirred again for 2 hours the mixture was extracted three times The combined organic phases were washed twice with 30 ml of water each time dried concentrated under reduced pressure The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1.9 g (14.08 mmol) of potassium carbonate were added at 60° C. to a suspension of 2.25 g (8.8 mmol) of 7-benzyl-3-methylxanthine (prepared according to Example 1 a) in 50 ml of N-methylpyrrolidone and the mixture was stirred at this temperature for one hour. 1.4 g (11.44 mmol) of isobutoxymethyl chloride were then added dropwise and the mixture was stirred at 80° C. for 3 hours. A further 0.5 g (4.4 mmol) of isobutoxymethyl chloride was then added and the mixture was stirred again for 2 hours. 50 ml of water were then added and the mixture was extracted three times using 60 ml of methyl tert-butyl ether each time. The combined organic phases were washed twice with 30 ml of water each time, dried using magnesium sulfate and concentrated under reduced pressure. The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2). prepared the mixture was stirred at 80° C. for 3 hours the mixture was stirred again for 2 hours the mixture was extracted three times The combined organic phases were washed twice with 30 ml of water each time dried concentrated under reduced pressure The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1.9 g (14.08 mmol) of potassium carbonate were added at 60° C. to a suspension of 2.25 g (8.8 mmol) of 7-benzyl-3-methylxanthine (prepared according to Example 1 a) in 50 ml of N-methylpyrrolidone and the mixture was stirred at this temperature for one hour. 1.4 g (11.44 mmol) of isobutoxymethyl chloride were then added dropwise and the mixture was stirred at 80° C. for 3 hours. A further 0.5 g (4.4 mmol) of isobutoxymethyl chloride was then added and the mixture was stirred again for 2 hours. 50 ml of water were then added and the mixture was extracted three times using 60 ml of methyl tert-butyl ether each time. The combined organic phases were washed twice with 30 ml of water each time, dried using magnesium sulfate and concentrated under reduced pressure. The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2). prepared the mixture was stirred at 80° C. for 3 hours the mixture was stirred again for 2 hours the mixture was extracted three times The combined organic phases were washed twice with 30 ml of water each time dried concentrated under reduced pressure The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2)

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 7.1 g (20 mmol) of 6-(4-chlorophenyl)-4-hydroxy-5-methyl-3-(2,4,6-trimethyl-phenyl)-2-pyrone in 50 ml of ethyl acetate are introduced in the absence of moisture. 2.02 g (20 mmol) of triethylamine are added thereto at 20° C. and a solution of 2.4 g (20 mmol) of i-butoxychloromethane in 20 ml of ethyl acetate is added dropwise at 0° C. with cooling. The mixture is then further stirred for 20 h at 20° C. and the reaction is followed by thin-layer chromatography. The solution is filtered off from the precipitated triethylamine hydrochloride using suction and washed with ethyl acetate. The combined mother liquors are washed twice, each time with 50 ml of half-saturated common salt solution, dried over magnesium sulfate and evaporated in vacuo. 8.8 g of crude product are obtained. 5.6 g (63% of theory) of 6-(4-chlorophenyl)-4-[(2-methyl-1-propoxy)-methoxy]-5-methyl-3-(2,4,6-trimethylphenyl)-2-pyrone are obtained as an oil by flash chromatography on 500 g of silica gel 60 (35-70 μm) using toluene:acetone 50:1 as mobile phase. with cooling The solution is filtered off from the precipitated triethylamine hydrochloride using suction washed with ethyl acetate The combined mother liquors are washed twice each time with 50 ml of half-saturated common salt solution, dried over magnesium sulfate evaporated in vacuo 8.8 g of crude product are obtained

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1.9 g (14.08 mmol) of potassium carbonate were added at 60° C. to a suspension of 2.25 g (8.8 mmol) of 7-benzyl-3-methylxanthine (prepared according to Example 1 a) in 50 ml of N-methylpyrrolidone and the mixture was stirred at this temperature for one hour. 1.4 g (11.44 mmol) of isobutoxymethyl chloride were then added dropwise and the mixture was stirred at 80° C. for 3 hours. A further 0.5 g (4.4 mmol) of isobutoxymethyl chloride was then added and the mixture was stirred again for 2 hours. 50 ml of water were then added and the mixture was extracted three times using 60 ml of methyl tert-butyl ether each time. The combined organic phases were washed twice with 30 ml of water each time, dried using magnesium sulfate and concentrated under reduced pressure. The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2). prepared the mixture was stirred at 80° C. for 3 hours the mixture was stirred again for 2 hours the mixture was extracted three times The combined organic phases were washed twice with 30 ml of water each time dried concentrated under reduced pressure The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2)